It is common for individuals to use ladders to climb tall structures. For example, a worker may need to elevate themselves to a window to clean the window or a painter may need to elevate themselves up a wall to paint upper portions of the wall.
Common ladders are extension ladders and step ladders. An extension ladder may include a base and one or two upper sections that slide up and down to allow a user to reach different heights. Examples of extension ladders are telescoping ladders and straight ladders. Telescoping ladders can extend to reach various heights, and straight ladders have only a single section. In use, an extension ladder is usually leaned up against a generally vertical surface that is being climbed. A step ladder may have an A-frame design for being vertically supported without leaning on a vertical surface.
Sometimes it is necessary to climb narrow structures such as trees or poles. For example, a tree trimmer may need to lean a ladder against a tree, or an electrician may need to lean a ladder against an electrical pole. However, current ladder configurations are not configured to be safely leaned against such narrow structures. For example, a common extension ladder may have a width (e.g. a distance between side rails) that is much greater than a diameter of a tree or pole, which may cause the ladder to wobble against the tree or pole while being climbed.
Various patents exist that attempt to solve the above problem. However, the configurations in these patents are either too difficult to use, too difficult and complicated to manufacture, too difficult to store, too limited in their compatibility with variously sized narrow structures, or are too unstable to be leaning against a narrow structure while being climbed.
Accordingly, there exists a need for an improved ladder that is stable while leaning against narrow structures or surfaces.